Over the last few decades interest in soil organic carbon (SOC) has increased due to its role in C sequestration in terrestrial ecosystems, which could contribute to decreasing atmospheric CO2 levels. Therefore, attempts to model SOC content have multiplied over this time. In many studies, independent variables were related to SOC, however, the possible combined effects of different independent variables and their ability to model SOC have not been considered. In this study, 612 soil profiles obtained from the Natura 2000 network of protected areas in the Sierra Morena mountains, Spain were used to define the relationship between SOC and nitrogen content and 24 independent variables. Subsequently, using a multiple linear regression analysis (MURASOC), the effects of these variables on the correlation with SOC content were considered. Finally, the best parameters determined with the regression analysis were used in a climatic change scenario. The information generated in this study might support new strategies in decision-making to complete analyses started long ago and, once that is done, provide important information for soil management and climate adaptation strategies.